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31.
The Complex Links between Governance and Biodiversity 总被引:1,自引:0,他引:1
CHRISTOPHER B. BARRETT CLARK C. GIBSON† BARAK HOFFMAN† MATHEW D. McCUBBINS † 《Conservation biology》2006,20(5):1358-1366
Abstract: We argue that two problems weaken the claims of those who link corruption and the exploitation of natural resources. The first is conceptual and the second is methodological. Studies that use national-level indicators of corruption fail to note that corruption comes in many forms, at multiple levels, that may affect resource use quite differently: negatively, positively, or not at all. Without a clear causal model of the mechanism by which corruption affects resources, one should treat with caution any estimated relationship between corruption and the state of natural resources. Simple, atheoretical models linking corruption measures and natural resource use typically do not account for other important control variables pivotal to the relationship between humans and natural resources. By way of illustration of these two general concerns, we used statistical methods to demonstrate that the findings of a recent, well-known study that posits a link between corruption and decreases in forests and elephants are not robust to simple conceptual and methodological refinements. In particular, once we controlled for a few plausible anthropogenic and biophysical conditioning factors, estimated the effects in changes rather than levels so as not to confound cross-sectional and longitudinal variation, and incorporated additional observations from the same data sources, corruption levels no longer had any explanatory power. 相似文献
32.
Amplifying Nuclear and Mitochondrial DNA from African Elephant Ivory: a Tool for Monitoring the Ivory Trade 总被引:1,自引:0,他引:1
KENINE E. COMSTOCK† ELAINE A. OSTRANDER SAMUEL K. WASSER†‡ 《Conservation biology》2003,17(6):1840-1843
Abstract: The ability to extract DNA from ivory provides the basis for genetically tracking the origin of poached ivory and thus has important implications for elephant conservation and management. We describe a method to isolate and amplify both genomic and mitochondrial DNA from African elephant ivory that requires very small amounts of ivory taken from any location on the tusk. We pulverized ivory and isolated DNA with a modified QIAamp kit. Ivory as old as 10 to 20 years, stored at ambient conditions, was amenable to DNA isolation with this method. The isolated DNA was robustly amplified at 16 elephant microsatellite loci and two mitochondrial DNA loci. This method has important applications for the forensic analysis of poached African elephant ivory. It enables determination of where stronger antipoaching efforts are needed and provides the basis for monitoring the extent of the trade as well as the consequences of future international trade decisions. 相似文献
33.
Backward linkages refer to the various inter-firm relationships connecting an industry with its supply chain. Demand–supply interactions between producer firms and suppliers of original equipment, strategic inputs, components and specialised services have played an important role in the evolution of the South African mining sector, contributing indirectly to employment creation, new business growth and expansion, improved efficiency of mining operations, and new knowledge generation. This paper presents a case study of backward linkage development in the South African platinum group metals (PGM) industry and draws on the findings from a quantitative and qualitative analysis of the sector undertaken in 2007. A profile of the supply chain is provided and an assessment made of the strength and sustainability of existing linkages. 相似文献
34.
This paper focuses on changing patterns of substance use among low income, African American drug users evacuated from New Orleans, Louisiana, during Hurricane Katrina of August 2005. It examines the relationship between increases and decreases in alcohol and tobacco (AT) use and illicit drug (ID) use after Katrina and pre‐disaster and within‐disaster factors. Data from structured interviews with 200 Katrina evacuees currently living in Houston were collected 8–14 months after the disaster. Multivariate analysis revealed that rises in AT use were positively associated with education. Females and younger evacuees were more likely to have increased AT use. ID use increase was positively associated with resource loss and leaving the city before Katrina. Decreases in AT and ID use were found to be associated with disaster‐related exposure. The paper discusses the specific consequences of disasters on disadvantaged minority substance users and the importance of developing public health disaster policies that target this population. 相似文献